Correlations between the expression levels of micro-RNA146b, 221, 222 and p27Kip1 protein mRNA and the clinicopathologic parameters in papillary thyroid cancers.

CONTEXT: It has been shown that miRNA 221, 222 and 146b are increasingly expressed while p27(Kip1) is suppressed in papillary thyroid cancer (PTC). OBJECTIVE: We investigated the association between the disease recurrence risk and the expression of miRNA 221, 222, 146b and p27(Kip1) protein mRNA in these tumors. We also measured the changes in miRNAs in the presence of Hashimoto's thyroiditis (HT). METHODS: We examined formalin fixed tissue samples obtained from 77 patients. 11 out of 77 samples were identified as well differentiated tumor with uncertain malignant potential (WDT-UMP), 46 were PTC and 20 were normal thyroid tissue. RESULTS: Data analysis revealed that the higher risk of recurrence was associated with the higher miRNA expression levels in thyroid cancers. Higher expression levels of miRNA 146b, 221 and 222 were detected in thyroid cancer patients presenting with capsule invasion, vascular invasion or lymph node metastasis, when compared to the patients lacking these features. Furthermore miRNA expression levels were found to be significantly elevated in patients with distant metastases. A negative correlation was found between the p27(Kip1) protein mRNA level and the expression levels of miRNA 221, 222 and 146b. While the expression levels of miRNA 221, 222 and 146b were found to be higher in the cases of WDT-UMP comparing to normal thyroid tissue, the p27Kip1 protein mRNA expression level was lower. No difference was found between the patients with HT and without HT regarding miRNAs expression levels. CONCLUSIONS: The expression levels of miRNA 221, 222 and 146b were found to be increased in cases of thyroid cancer with a high risk of recurrence. It is important to understand that these molecular changes such as miRNA expression may eventually be used to predict risk of recurrence.

Hsp70 from Cyprinion macrostomus macrostomus and Garra rufa obtuse: stability and stability-dependent activity.

Two fish species, Cyprinion macrostomus macrostomus and Garra rufa obtuse, tolerate adverse conditions in the Kangal hot springs and cope with multiple stressors such as food deprivation, extreme temperature, toxins, protein degradation, hypoxia, and microbial damage. These fish have evolved strategies to counteract the stressors including the induction of heat shock proteins (Hsps). Hsps play an essential role in maintaining cellular homeostasis, and one of the key proteins in the mechanism is Hsp70. Hsp70 itself is exposed to the same stressors as all other proteins, and, hence, the stability of Hsp70 was investigated. For this purpose, Hsp70 ATPase activity was determined at different urea concentrations. It was found that the protein maintains considerable ATP hydrolysis activity at higher denaturant conditions. Temperature effects on the substrate peptide binding showed that Hsp70s bind prominently at elevated temperatures. Furthermore, temperature effects on Hsp70 aggregation indicated that the presence of nucleotides decreases the aggregation process. The present work has determined the stability and activity of cmHsp70 and grHsp70 themselves under extreme conditions. The stability of the Hsp70 proteins maintains substrate proteins in the native state, which may aid in the adaptation of the fish species to the hot spring environment.

A comparison of piezosurgery and conventional surgery by heat shock protein 70 expression.

The effects of mechanical instruments on the viability of cells are essential in terms of regeneration. There is considerable interest in cell repair following damage mediated by dental surgical procedures. Cells can tolerate stress by expressing heat shock protein 70 (Hsp70). During and after surgical tooth removal, oxidative stress can activate Hsp70 expression proportional to the intensity of the stress signal stimulus to cope with stress. This study examined the expression of Hsp70 as a potential biomarker of immediate postoperative stress in patients undergoing two different surgical procedures of different severity. Expression of Hsp70 both at mRNA and at protein level in the conventional group was two-fold higher than that of the piezo group. This suggests that tooth movement by the piezo method causes relatively lower stress in the alveolar bone. Piezosurgery provides relatively low stress to the patients and this may help cell repair after the surgical procedure. Patients undergoing more aggressive surgery using conventional methods showed a significant increase in Hsp70 in the immediate postoperative period. Therefore, Hsp70 induction can be a potential tool as a prognostic surgical marker.